Copper Pipe

In my view there are several aspects to why people don't believe in large water changes:

1) small water changes are quick and easy - everyone wants convenience so they don't think about any other way
2) other people tell them to only do 10/20/30% as more is dangerous and this perpetuates the myth
3) fish that have managed to survive in their own waste for months will die after a large water change - not because the water is damaging but because the stale water has changed the parameters (specifically acidity) so much that they die of shock when normal parameters are returned. "Old Tank Syndrome".

The existence of Old Tank Syndrome then reinforces the view that large water changes are dangerous as people attribute the deaths to the water change and fail to see the significance of a history of insufficient water changes. This leads back to point 2 which leads to point 1. And so the myth persists.

well there's ways of doing this automatic...
drill the tank if it isn't already...connect it to a drain and put a mesh on the pvc pipe going into the drain...(around 10 bucks)

next..get a tds controller..you can buy a ph/tds combo on aliexpress for around 100 bucks

put it in and start doing only 1 week water changes and check how much the tds is right before you do a water change
then set the ceiling of the tds range to that number
then grab a solenoid water dispenser/pump and a universal plug 10-40 bucks on amazon or around 35bucks the whole set...solenoid water dispenser + plug

connect this to the tds controller and to your water source and the psi from your water source will push the water through it when the solenoid valve opens
you can also connect a water bottle with prime using one of those brine shrimp hatchery connectors from ebay/amazon so you only allow a few drops when the water runs
(it has to be connected on the water source side of the solenoid water valve to have the valve close and not allow prime to drip into the pipe..)
(and you have to make a hole in the prime water bottle and put a one way valve glued in that hole to allow air into the bottle and allow the prime to go into the water pipe)
as for water changes..different people will say more is better others less is better..
I don't believe many actually test for when the water should be changed...
my tds after a water change is around 320 and I change it at 400
consistency no matter how big of a water change is key...if you do 3% daily which is around 21% weekly and it works for you...just stick with it
as for using copper in your tanks:
you have a paper here about it and why it should not be used: https://edis.ifas.ufl.edu/publication/FA165
good luck on your journey on making things easier and pics are always nice to see ;]

Naughts said:

In my view there are several aspects to why people don't believe in large water changes:

1) small water changes are quick and easy - everyone wants convenience so they don't think about any other way
2) other people tell them to only do 10/20/30% as more is dangerous and this perpetuates the myth
3) fish that have managed to survive in their own waste for months will die after a large water change - not because the water is damaging but because the stale water has changed the parameters (specifically acidity) so much that they die of shock when normal parameters are returned. "Old Tank Syndrome".

The existence of Old Tank Syndrome then reinforces the view that large water changes are dangerous as people attribute the deaths to the water change and fail to see the significance of a history of insufficient water changes. This leads back to point 2 which leads to point 1. And so the myth persists.

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I am so glad to see this posted! I couldn't find better words to make this point! I have come to a point in my fishkeeping hobby where I make things simple, one of them is a 50% to 75% water change weekly (more or less)
When it comes to this large of a water change the thing to keep in mind is that the tap water is consistent to a certain degree, you're almost changing their whole environment in a matter of minutes, so temperature, pH and de-chlorination is something to be aware of. The proof is in the pudding and how fish look and react right after.
Adding to this, why not build some sort of plumbing that would make it easier for you to connect a hose to your nearest sink for your water changes? But that's providing you have a sink nearby.

Just a quick note to confirm that I do at least 3% per day. So approx. 21% per week not 3% per week.

sparkypenguin said:

Hi all,

I am currently experimenting with various methods of tank hoovering in an attempt to make it as easy as possible for me and as stressless as possible for the fish etc.
My current version will include a length of COPPER pipe that sits outside of the tank that will be permanently filled with tank water.
The idea being that I connect the hoover pipe to the top of this length of COPPER pipe and then open a valve at the bottom of this length of pipe.
As the water exists the bottom of the COPPER pipe it will create a vacuum behind it and start the syphon project.
The syphoned water will then be filtered and returned to the tank and hence my question is can I use COPPER pipe.
I have Phantom Tetras, Platys, Mollies, Bristlenose Plecs, Panda Cories, Apple snails, Nerite Snails and would like to introduce loaches at some point.
Please
Kind regards,
Mark.

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The main reason I do water changes is to lower the level of nitrates in the water. You need to discard the old tank water in order to do this. If your tank has been established for a while, let's say two months, you will have progressed through the nitrogen cycle, and the ammonia will have been converted to nitrites, and the nitrites to nitrates. This is an ongoing, never ending cycle, but in a stable tank the end point is a level of nitrates that the fish population will tolerate. This will however build to intolerable levels unless you do a water change, generally not more than 25-30% changed in one water change to avoid stressing the fish to much. Same temperature water in as out. Dechlorinated water in, either before putting it in or shortly after. I do this water change monthly and I keep a log of the water change, and chemical modifiers added to the water (in my case I use Amquel and Novaqua Plus). My tanks have been set up for many years with a stable fish population.

sparkypenguin said:

Just a quick note to confirm that I do at least 3% per day. So approx. 21% per week not 3% per week.

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This math is not accurate. When you change 3% on day 1, you leave 97% of the pollution in the tank. The next day you start out with this 97% plus whatever has accumulated since the previous day--and at the level that most of us stock out tanks this is a considerable amount of pollution entering the tank every single day--so you actually have more pollution in the tank on day 2. You remove 3% again, leaving more behind than you left behind the day previous, and so on. So at the end of the week, the tank water is far more polluted than it was at the beginning of that week.

By contrast, if you remove 70% on day 1, you will have no more on day 7 because the pollution occurring every day is slowly building up but it never becomes greater from week to week with the substantial weekly water change.

You really cannot logically argue the issue of water changes. Discus breeders often change 90% of the tank water in fry tanks not just once but some of them twice every single day. And the fish grow healthier for doing this, so the proof is in the pudding.

sparkypenguin said:

Just a quick note to confirm that I do at least 3% per day. So approx. 21% per week not 3% per week.

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Percentages required are arbitrary but this is still woefully inadequate.

One thing that hasn't been mentioned is minerals and other nutrients in tap water, that aren't being replenished by using old tank water to (re)fill a tank.

I have a good use for old tank water, though....watering my potted plants & flowerbeds

I agree with most everything said but the math 3% per day being equivalent to 21% over the week is effectively correct. Assuming a nitrate buildup due to fish waste at 2.5 ppm per week and the input water at 0ppm Nitrate (this works with concentration of other contaminants):

• 3% daily water changes results in an average value of 11.6 ppm with a max of 11.8 ppm just before a change is made.
• 21% weekly water changes results in an average value of 10.2 ppm with a max of 11.8 ppm just before a change is made.

In the case of 3% daily you have less variation in the NO3 value because you are always removing a small amount of the contaminant daily. In the case of the 21% weekly you remove a larger amount but you also build up a larger amount, additionally the for both schedules the max levels of NO3 are identical to 3 decimal places.

In regards to the fish the water change schedule and amount changed should be based on the following:
- How fast the Nitrates and other contaminants build up, without new additions to a tank this should be pretty constant over the long term. (affects amount changed)
- How much variation in concentration the fish can handle without being stressed (Affects frequency - usually more frequent)
- What is the maximum concentration you would want to see (Affects amount changed)
- Time it takes to setup for a water change, and the time it takes to do one (Affect frequency - usually less frequent)

The point being that 50% weekly change is effectively equivalent to 7% daily. Both would work if you need to remove 50% of the water after a week. I would like to stress that Nitrate is only one contaminant that we can measure, there are other contaminants the build up in the water that we cannot measure. Larger volumes will generally give better results as long as the water is not "adjusting" after being placed in the tank (ie acid water added to a neutral pH tank that uses limestone or shells in the water to elevate the KH, where smaller more frequent changes would be more appropriate)

Below is 3% changes at a low rate of NO3 production of 2.5 ppm per week. NO3 conc. stabilizes at 11.7ppm. Horizontal Axis is days, Vertical is ppm.


Below is 21% changes at the same NO3 production rate:

Measuring nitrate here is pretty much a waste to prove your point. If you want to get a real idea of what is going on in your tank, you need to measure conductivity or TDS. The latter is easier and likely cheaper. They will measure everything in the water.

Next, and most importantly, of all the test kits we use in the hobby, the ones for nitrate are the least accurate, This is especially true under 20 ppm.

Next, your weekly nitrate production assumption is pretty low. Most test kits measure on the total ion scale which means for each 1 ppm of Total Ammonia (NH3 + NH4) you can end up with as much as about 3.88 ppm of nitrate. So that means for you to have only 2.5 ppm/week, you can only be producing 0.644 ppm of ammonia every 7 days which means am max of 0.092 ppm of ammonia every 24 hours in the tank.

The only way the average well stocked aquarium can only produce a testable 2.5 ppm of NO2 in a week is if it is very heavily planted.

There is more to water changes than just what you remove. Over time things in the water that are needed will get used up. Other things will not be used at all and will accumulate over time,

Carbonates and bicarbonates in the water of our tanks is what helps to hold the pH stable. But the nitrifying bacteria need inorganic carbon and they get this from carbonates and bicarbonates as well as CO2.

Additionally, the cycle itself is acidic. Both Nitrite and Nitrate create acid in the water. What slows this is KH. This is why in old tank syndrome the pH drops a lot. There is one benefit to this. Most or all of the ammonia in the water will be in the form of ammonium (NH4) which is way less toxic than ammonia (NH3).

The there is a host of things in very small amounts need in the water to help keep the fish healthy which are also being used up.

So not only do water changes remove the bad stuff in the water which should not be allowed to accumulate they restore essential things to the water.

I have only been keeping tanks for almost 23 years unlike some of the more experienced folks here. I have been doing weekly big (50%+) water changes an many tanks from day one. My fish love this. Most tend to hide durning maint. But when the tank is refilled and I have stopped working in it, most of the fish come and "play." Some will even spawn soon after in response to such water changes.

Also, in all the time I have been in the hobby I have never heard of fish dying because their water was too clean.

TwoTankAmin said:

Measuring nitrate here is pretty much a waste to prove your point. If you want to get a real idea of what is going on in your tank, you need to measure conductivity or TDS. The latter is easier and likely cheaper. They will measure everything in the water.

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I tend to agree, Nitrates are a measure that is easily available but not necessarily accurate. The concept daily vs weekly changes in regards to TDS or conductivity would be the same. My point still is that in regards to removing impurities changing the water once a day vs once a week has little influence as long as the total amount of water is removed is the same.

The 2.5 ppm per week of nitrate comes from my tank which is planted but also has a small number of fish, 4 angels and 3 tetras in a 75 gallon tank.

Uberhoust said:

I tend to agree, Nitrates are a measure that is easily available but not necessarily accurate. The concept daily vs weekly changes in regards to TDS or conductivity would be the same. My point still is that in regards to removing impurities changing the water once a day vs once a week has little influence as long as the total amount of water is removed is the same.

The 2.5 ppm per week of nitrate comes from my tank which is planted but also has a small number of fish, 4 angels and 3 tetras in a 75 gallon tank.

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OT, but, THREE tetras, in a 75G???

So wrong, for so many reasons ... bordering on blasphemy*

*I kid, of course...the characins are my favorite fish...I'd have a tank of that size full of them...and of course, all tetras need to be in large groups, which I'm sure you know

With respect to anyone thinking differently, I still consider a large weekly change of far more benefit than smaller more frequent changes. I hold this view because it seems reasoned from the research, so here is an article from TFH on this exact topic. It convinces me.

To add to the above

Thanks to everyone for all of their replies.

Based on the cumulative knowledge of all......

Returning to the OP question I have decided to use plastic pipe rather than copper and to stop returning water back to the tank.

And on the much discussed topic of water changes.....
When I have recalculated I actually change about 4.7% per day which equates to 32.9% per week however I've still decided to double this to approx. 66% per week as it only means 2 buckets rather than 1 per day.
I'm sticking to the daily changes rather than the weekly ones as it enables me to drip the water in via a bucket with a tap fitted and this lets the tank heaters maintain the correct tank temperature and I also still believe that daily water changes are better than weekly (if the overall volume is sufficient) as it will minimise any risk of sudden changes to the water parameters.
@Byron - I wrote this before your last TFH article post so I may change my mind once I have read it!

To answer a few of the recent questions / suggestions...

@kiko
The set up you have described looks really good but a little OTT for me at the moment, however I am currently building a house and my aim is to build a very large tank at some point. Not sure how big but your automated system may well come in handy.
And as requested I have attached a photo

@gilpi
I wish I could plumb the tank in directly but due to it's location it's simply not possible. However as per above I am planning to build a much bigger tank in a house I am building and the plan is to have some form of automated system that continually changes the water.

Although my original question was a simple one about copper pipe the thread somehow managed to grow into a detailed water change discussion. This morphing of topics is what I like so much about this forum as it's continually helping me to improve my knowledge and more importantly my tank inhabitants quality of life. So a big thanks to everyone who has taken so much time to go into such detail.